1 files changed, 29 insertions, 21 deletions

diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 52d5d26fc7c6..b2e3d0b0a116 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -97,6 +97,14 @@ static inline int which_bucket(u64 duration_ns)
 
 static DEFINE_PER_CPU(struct menu_device, menu_devices);
 
+static void menu_update_intervals(struct menu_device *data, unsigned int interval_us)
+{
+	/* Update the repeating-pattern data. */
+	data->intervals[data->interval_ptr++] = interval_us;
+	if (data->interval_ptr >= INTERVALS)
+		data->interval_ptr = 0;
+}
+
 static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev);
 
 /*
@@ -222,6 +230,14 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 	if (data->needs_update) {
 		menu_update(drv, dev);
 		data->needs_update = 0;
+	} else if (!dev->last_residency_ns) {
+		/*
+		 * This happens when the driver rejects the previously selected
+		 * idle state and returns an error, so update the recent
+		 * intervals table to prevent invalid information from being
+		 * used going forward.
+		 */
+		menu_update_intervals(data, UINT_MAX);
 	}
 
 	/* Find the shortest expected idle interval. */
@@ -271,20 +287,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 		return 0;
 	}
 
-	if (tick_nohz_tick_stopped()) {
-		/*
-		 * If the tick is already stopped, the cost of possible short
-		 * idle duration misprediction is much higher, because the CPU
-		 * may be stuck in a shallow idle state for a long time as a
-		 * result of it.  In that case say we might mispredict and use
-		 * the known time till the closest timer event for the idle
-		 * state selection.
-		 */
-		if (predicted_ns < TICK_NSEC)
-			predicted_ns = data->next_timer_ns;
-	} else if (latency_req > predicted_ns) {
-		latency_req = predicted_ns;
-	}
+	/*
+	 * If the tick is already stopped, the cost of possible short idle
+	 * duration misprediction is much higher, because the CPU may be stuck
+	 * in a shallow idle state for a long time as a result of it.  In that
+	 * case, say we might mispredict and use the known time till the closest
+	 * timer event for the idle state selection.
+	 */
+	if (tick_nohz_tick_stopped() && predicted_ns < TICK_NSEC)
+		predicted_ns = data->next_timer_ns;
 
 	/*
 	 * Find the idle state with the lowest power while satisfying
@@ -300,13 +311,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 		if (idx == -1)
 			idx = i; /* first enabled state */
 
+		if (s->exit_latency_ns > latency_req)
+			break;
+
 		if (s->target_residency_ns > predicted_ns) {
 			/*
 			 * Use a physical idle state, not busy polling, unless
 			 * a timer is going to trigger soon enough.
 			 */
 			if ((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) &&
-			    s->exit_latency_ns <= latency_req &&
 			    s->target_residency_ns <= data->next_timer_ns) {
 				predicted_ns = s->target_residency_ns;
 				idx = i;
@@ -338,8 +351,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 
 			return idx;
 		}
-		if (s->exit_latency_ns > latency_req)
-			break;
 
 		idx = i;
 	}
@@ -482,10 +493,7 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
 
 	data->correction_factor[data->bucket] = new_factor;
 
-	/* update the repeating-pattern data */
-	data->intervals[data->interval_ptr++] = ktime_to_us(measured_ns);
-	if (data->interval_ptr >= INTERVALS)
-		data->interval_ptr = 0;
+	menu_update_intervals(data, ktime_to_us(measured_ns));
 }
 
 /**